Midwest Dairy Foods Research Center, University of Minnesota, St Paul 55108, USA.
J Dairy Sci. 2011 Oct;94(10):4843-9. doi: 10.3168/jds.2011-4549.
Calcium and lactate are present in excess of their solubility in Cheddar cheese. Consequently, calcium lactate crystals (CLC) are a common defect in Cheddar cheese. A novel approach for preventing CLC is the addition of sodium gluconate. Sodium gluconate has the potential to increase the solubility of calcium and lactate by forming soluble complexes with calcium and lactate ions, and preventing them from being available for the formation of CLC. The objective of this study was to determine if sodium gluconate could increase the solubility of calcium lactate (CaL(2)). Seven CaL(2) solutions (5.31% wt/wt) with 7 levels of sodium gluconate (0, 0.5, 1, 1.5, 2, 3, and 4% wt/wt) were made in triplicate. Solutions were stored at 7 °C for 21 d, and were visually inspected for CLC formation. Subsequently, they were filtered to remove CLC and the supernatant was analyzed for lactic acid and gluconic acid by HPLC and for calcium by atomic absorption spectroscopy. The visual inspection demonstrated that CLC were formed in the solution with 0% gluconate after the first day of storage and CLC continued to accumulate over time. A minute amount of CLC was also visible in the solution with 0.5% gluconate after 21 d of storage, whereas CLC were not visible in the other solutions. The HPLC results indicated a higher concentration of calcium and lactic acid in the filtrate from the solutions containing added gluconate. Thus, sodium gluconate can increase the solubility of CaL(2).
在切达干酪中，钙和乳酸的含量超过了它们的溶解度。因此，乳酸钙晶体（CLC）是切达干酪中的一种常见缺陷。一种防止 CLC 的新方法是添加葡萄糖酸钠。葡萄糖酸钠有可能通过与钙和乳酸离子形成可溶性络合物来增加钙和乳酸的溶解度，从而防止它们形成 CLC。本研究的目的是确定葡萄糖酸钠是否能提高乳酸钙（CaL（2））的溶解度。在 7°C 下储存 21 天，并目视检查 CLC 形成情况。随后，将其过滤以去除 CLC，并通过 HPLC 分析上清液中的乳酸和葡萄糖酸，以及原子吸收光谱法分析钙。目视检查表明，在没有葡萄糖酸钠的溶液中，在储存的第一天就形成了 CLC，并且随着时间的推移，CLC 继续积累。在储存 21 天后，含有 0.5%葡萄糖酸钠的溶液中也可以看到少量的 CLC，但在其他溶液中则不可见。HPLC 结果表明，添加葡萄糖酸钠的溶液的滤液中钙和乳酸的浓度更高。因此，葡萄糖酸钠可以提高 CaL（2）的溶解度。
